Carlos Alberto Sainz (born 13 December 1937) is a former Argentine association football player.
Sainz began his career in 1958 at Argentinos Juniors, where he played until 1961.
He stayed at River Plate until 1967 and then moved to San Lorenzo from Mar de Plata in 1968 before retiring in 1969.
Sainz was member of the Argentina squad at the 1962 FIFA World Cup, where Argentina were eliminated in the group stage.
He appeared in groups stage matches against Bulgaria and Hungary.